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Frylock
07-03-2012, 02:06 PM
I need to know how to read the notation on page three of this article: http://fitelson.org/few/few_05/egan.pdf

I know almost nothing about how to read the notation I'm looking at. The sigma has something to do with... summing something up, I think. Is that the 'v' of disjunction or something else? I know the probability notation in the first parentheses--but is the second parentheses enclosing a product (of H and A) or does juxtaposition not mean products here? If a product, how do you compute the product of a set of worlds and an action? Where did that random 'c' come from?

Thanks for any pointers...

Frylock
07-03-2012, 02:08 PM
I think the 'c' represents something like a "credence function," though I'd like to read a little more about how that'd be defined.

Thudlow Boink
07-03-2012, 02:19 PM
I think the SigmaH is supposed to be the sum over all the H's ("the Hs form a partition of the worlds"). In other words, for each "world" H, evaluate c(H|A)v(HA), and add all those values together. However you do that. Dunno if that helps.

The typesetting's a bit confusing. At first I thought the c was a superscript on the H, perhaps meaning "complement," but seeing how it was used elsewhere in the article rules that out.

Frylock
07-03-2012, 02:24 PM
I think the SigmaH is supposed to be the sum over all the H's ("the Hs form a partition of the worlds"). In other words, for each "world" H, evaluate c(H|A)v(HA), and add all those values together. However you do that. Dunno if that helps.

The typesetting's a bit confusing. At first I thought the c was a superscript on the H, perhaps meaning "complement," but seeing how it was used elsewhere in the article rules that out.

I think you're right. Now I just need to know what is meant by that "v" and that "HA".

ultrafilter
07-03-2012, 02:37 PM
The go-to book on causality is Judea Pearl's Causality (http://www.amazon.com/Causality-Reasoning-Inference-Judea-Pearl/dp/052189560X/). This is not something that the average mathematician will be at all familiar with, so you're best off going straight to the source.

Edit: I'm not familiar enough with this stuff to swear that what you're looking for is in there, but it's definitely the first place I'd look.

Frylock
07-03-2012, 02:56 PM
The go-to book on causality is Judea Pearl's Causality (http://www.amazon.com/Causality-Reasoning-Inference-Judea-Pearl/dp/052189560X/). This is not something that the average mathematician will be at all familiar with, so you're best off going straight to the source.

Edit: I'm not familiar enough with this stuff to swear that what you're looking for is in there, but it's definitely the first place I'd look.

I'll think about taking a look at it (a lot of money to cough up though, and trips to the library these days are difficult with baby twins in tow...) but from here it looks a little more like "throw me in the deep end and yell at me to swim" than "teach me how to read" material...

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